With the Yankees' playoff hopes on life support entering the final month of the season, it appears that the biggest storyline for the team in September will be the (not) farewell tour of Derek Jeter.

However, Jeter's final at-bats in a Yankee uniform likely won't be the only history that fans will witness down the stretch....

If the Yankees maintain their current season pace, they would become the first team in major-league history to post back-to-back winning seasons while being outscored by at least 20 runs in each year.

Last season the Yankees went 85-77 despite a run differential of -21, their worst mark since 1991 (-103). Based on the amount of runs scored and allowed, the team was expected to win just 79 games.

This year they could easily end up with an even lower run differential and still produce a winning record – they currently have been outscored by 27 runs and are five games over .500.

Since they became known as the Yankees in 1913, the only other time they recorded consecutive seasons with a run differential of -20 or worse was arguably the darkest period in franchise history: a three-year stretch from 1989-91, during which the team had three different managers and averaged only 71 wins per season.

The Secret Sauce
The reasons for the Yankees outperforming their expected record in 2013 and 2014 are pretty clear.

The team has played extremely well in close games, going a combined 92-60 (.605) in games decided by two runs or fewer since last year, which is easily the best such record in MLB over the last two seasons. They led the majors in 2013 with a 50-30 record and are tied with the Orioles for the best record this season (42-30).

And they have been on the losing end of a lot of blowouts, going 29-38 in games decided by five or more runs, one of the worst marks in baseball since 2013. This disparity in their record in close/blowout games easily skews their run differential into the red.

Some people may argue that the Yankees have been “lucky” to win these close games. But the fact that they have done so in consecutive years probably means that more than simple luck is involved.

So what has been the Yankees' “secret sauce” during this historical run of beating their expected record over the last two seasons?

It should come as no shock that a dynamic, late-inning offense is not the reason why the Yankees have done so well in close games. Over the last two seasons, only the Marlins have a worse OPS in “close and late situations” (the 7th inning or later with the batting team ahead by one run, tied, or with the tying run on base, at bat or on deck) than the Yankees.

Instead it has been a clutch pitching staff – led by motley crew of bullpen arms - that has helped the team emerge as winners in a high percentage of these tight contests over the last two years.

• Yankees pitchers have allowed an on-base percentage of just .296 in “close and late situations” since 2013, third-best in the majors during that span;

• Their OPS allowed when the score is within two runs at any point in the game is just .678, ranking sixth in MLB since 2013;

• Only the Athletics and Reds have allowed a lower WHIP in high-leverage plate appearances than the Yankees (1.09) over the last two seasons.

Simply put, the Yankees' late-inning guys are not letting batters get on base in these close games, keeping enough runs off the board to either preserve the team's slim lead or give the anemic offense a chance to win with a rare clutch hit or two.

So after the Yankees postseason odds inevitably reach zero this season and as you count down the days until Number Two tips his cap for the final time, remember that there will be one statistical record within reach for this Yankee team... albeit one that may be more forgettable than remarkable.

And, needless to say, while the Yankees' current two-year stretch of defying their run differential at historic pace is quite a feat, it's one that most fans would gladly replace with a couple postseason appearances and meaningful games to watch in October.